Vacuum cleaner



F. CARLSTEDT VACUUM CLEANER June 23, 1936.

Filed Feb. 9, 1934 6 Sheets-Sheet l ,6.- ATTORNEY June 23, 1936. F. CARLSTEDT VACUUM CLEANER F iled Feb. 9, 1954 6 Sheets-Sheet 2 4 ATroRNEY June 23, 1936. F. CARLSTEDT VACUUM CLEANER Filed Feb. 9, 1934 6 Sheets-Sheet 5 VENTOR i-ZAJ W4, 44:. ATTORNEY June 23, 1936. CARLSTEDT 2,044,830

VACUUM CLEANER Filed Feb. 9, 1934' 6 Sheets-Sheet 4 IN ENTOR M 14 ATTORNEY June 23, 1936. F. CARLSTEDT VACUUM CLEANER Filed Feb. 9, 1934 6 Sheets-Sheet 5 INVENTOR M BY ATTQR Y June 23, 1936. F. CARLSTEDT 2,044,830

VACUUM CLEANER Filed Feb. 9, 1934 6 Sheets-Sheet 6 42, ATTORNEY atenied June 23, 1936 VACUUM CLEANER Fredrik Carlstedt, Stockholm, Sweden, assignor to Electrolux Corporation, Dover, Del., a corporation of Delaware Application February 9, 1934, Serial No. 710,421 In GermanyJuly 8, 1933 10 Claims.

In the use of vacuum cleaners, difierent conditions of cleaning make it desirable to have different conditions of vacuum cleaner action. For example, in cleaning overstuffed furniture, tapestries or the like, a high vacuum is desirable, while in cleaning a smooth floor, a large quantity of air is more desirable. In the first case, a high suction serves to draw air through the cloth or the like and to take up threads and the like attached to the fabric. A high vacuum is not necessary in cleaning a floor, but a large air quantity at lower pressure differential suffices and permits cleaning a given area in a quicker time. When using the cleaner for tapestries and the like the nozzle is preferably connected with the cleaner unit by means of a hose and possibly a hollow steel tube. In cleaning a smooth floor, it is desirable to use large nozzles, which are directly connected to the cleaner without the hose.

The present invention has for its principal object to efiiciently accomplish both the foregoing types of cleaning in one and the same apparatus and more particularly to provide mechanism for altering the flow of air through a plurality of air impellers so that the flow may be in parallel or in series; parallel flow corresponding to the larger quantity of air at lower pressure, and series flow corresponding to lower volume of air at higher suction.

The invention will be more clearly understood by reference to the accompanying drawings illustrating the invention and forming a part of this specification and of which:

Fig. 1 is an elevational view principally in cross section of a vacuum cleaner embodying the invention;

Fig. 2 is a similar view on an enlarged scale of part of the apparatus shown in Fig. 1;

Fig. 3 is atransverse sectional view taken on the line 3--3 of Fig. 2;

Fig. 4 is a view-similar to Fig. 2 but showing the parts in a diiferent position;

the line Ill-10 of Fig. 11 and showing still another form of the invention;

Fig. 11.is a sectional view taken on the line ll--ll of Fig. 10;

Fig. 12 is a top view of the mechanism shown 5 in Figs. 10 and 11;

Fig. 13 is a sectional view of a part of this embodiment;

Figs. 14 and 15 show different positions of an actuating mechanism, Fig. 14 beingtaken on the line l4- -l4 of Fig. 11;

Fig. 16 is a view similar to Fig. 10 but showing the parts in different relative positions;

Fig. 1'7 is taken on the line Il-l| of Fig. 16;

Fig. 18 is a transverse sectional view taken on the line 18-18 of Fig. 19 and showing an automatic mechanism for changing the relation of parts in the apparatus;

Fig. 19 is a view taken on the line |9l9 0 Fig. 18; a 20 Fig. 20 is similar to Fig. 18 and shows a dimerent relative position of parts;

Fig. 21 shows still another embodiment of the invention, the view being partly cut away to show an elevational cross-section; 25

Fig. 22 is a transverse sectional view taken on the line 22-22 of Fig. 21;

Fig. 23is a horizontal sectional view taken on the line 23-23 of Fig. 22;

Fig. 24 is an elevational view of another embodiment of the invention;

Fig. 25 is a view partly in section of the apparatus shown in Fig. 24; and

Fig. 26 is a cross-sectional view taken on the line 26-26 of Fig. 25. 35

Referring to the embodiment shown in Figs. 1 to 5, the vacuum cleaner includes a main cleaner unit Ill comprising a cylindrical barrel II, to which are attached end members I 2 and I3 secured to the barrel portion of the cleaner unit by any suitable means such as spring clips l4 and I 5. The unit may be horizontally mounted by means of runners 9. A coupling member l6 screws into the end cap l2 and serves for a connection with a hose I1 adapted to be connected to a cleaning tool or nozzle. A steel tube or wand I8 may be interposed between the nozzle and the hose. In the casing of the cleaner unit formed by the barrel II and the end caps l2 and I3 is a motor l9, preferably resiliently mounted. The 50 motor has a shaft 20 on which are mounted a forward fan impeller 2| and a rear fan impeller 22. The fan impellers preferably are of the turbine type having blades disposed between parallel discs.

Operation of the motor serves to rotate the fan impellers and thereby draw air through the hose l1 and through the casing inthe direction of the arrows and out through the outlet 23. Disposed in the casing and held in place by end cap I2 is a dust-bag 24 of air-pervious but dustimpervious material.

Disposed between the torward and rear fan impellers 2| and 22 is a partition member designated generally by reference numeral 25. Partition member 25 is secured to a housing 26 which surrounds the motor and rear fan impeller 22 and which may be attached to an insulation ring 21 on which the motor is resiliently mounted. It will be understood that the casing or housing member 26 is preferably fixed with respect to the barrel Partition member 25 has a front wall 28. Wall 28 is centrally apertured for the pas-' sage of shaft 28. Radially outward therefrom is a series of openings 29. Radially outward from the openings 29 is a plurality of rearwardly extending passageways -38 formed in box-like extensions which are secured to the member 26. The peripheral part of the member 25 is provided with apertures 3|. The openings 29, the passageways 38 and the apertures 3| correspond in number.

Rotatably mounted on member 25 is a disc member or valve member 32. A flanged nut or the like 33 holds the disc member 32 and an attached plate member 34 rotatably against the member 25. The valve disc 32 overlaps the member 25 peripherally and is provided with peripheral opening 35 which are adapted to register with the apertures 3|. Valve disc 32 is provided with apertures 31 adapted to register with passageways 35 and apertures 38 adapted to register with openings 29. The apertures 31 and 38 are radially out of alignment so that when the apertures 31 register with the passages 33 the openings 29 and 38 are shut; and when openings 29 and 39 register the openings '31 and passages 38 are closed. A manipulating knob 39 extends through the casing l I so as to be operable from the exterior of the cleaner, and is screwed into the rotatable disc member 32 and isadapted to move in a slot '48. In order to prevent leakage of air a shield 4| is provided which moves with the manipulating knob and closes the slot 49. A cover plate 42 is attached to disc member 32 and has a central aperture 43 for admission of air to the fan assembly covered by a shield 44 in the form of a perforated plate.

When it is desired to have a high vacuum, as when the hose I1 is connected and the cleaner is being used to clean overstufled furniture, the manipulating knob is moved to the position shown in Fig. 5. In this position of the parts, the air flows in through the central aperture 43, is forced outwardly in the fan impeller 2| and thence passes inwardly between parts 34 and 32, through the aligned openings 38 and 29, across the inner chamber of the member 25, into the center of fan impeller 22 and is thrown outwardly in fan impeller 22 and past the motor to the outlet 23. Thus the air passes through the impellers in series and the suction effect of the fan impellers is additive.

When it is desired to have a greater flow of air but high vacuum is not essential, as when cleaning floors, the long hose is preferably omitted and a large nozzle may be used and the manipulating knob is moved to the position shown in Figs. 2 and 3.- In this position, only part of the air flows in through central aperture 43 and into tures 31 and 38.

l center of fan member 2|.

fan impeller 2|, while the remainder flows outside hood 42 and in through the aligned apertures 3| and 35 and directly to the center inlet of the rear fan impeller 22. The air discharged from fan impeller 2| passes through openings 31 5 and passages 39 to the outlet of fan impeller 22. Thus, the air, which passes through fan member 2| does not pass through fan member 22; and the air passing through fan member 22 does not pass through fan member 2|.' In this position, the apertures 28 and 38 are out of alignment so that the series connection is blocked oiT. In the position shown in Figs. 4 and 5, the passages 38 are blocked 011 and the apertures 3| and 35 are not in alignment. In the position of Figs. 2 and 3, the air flowsin parallel through the fan members and the quantity is large but the pressure diilferential is only that of one fan impeller.

In the apparatus shown in Figs. 6 to 9, corresponding parts to those of the previously described embodiment are similarly designated. The member 32 in this case is a flat disc and the apertures 35 are in the same plane as the aper- The apertures 3| are on the plane part of the partition member 25. This apparatus operates in the same manner and the arrows show how the air passes in series through the fan members in Fig. 8 and in parallel in Fig. 6.

Figs. 10-17 show another embodiment of the 30 invention. Rigidly attached to the fan housing 26, as by bolts 46, is a plate member 41 having a central aperture 48 for admitting air to the inlet of the rear fan impeller 22 and outwardly disposed apertures 49 for admitting air to the discharge side of fan impeller 22. Rigidly secured to plate 41 as by screws 53 is a member 5|! having a forward circular wall 52 and rearwardly projecting angle pieces comprising radial parts 54 and peripheral parts 55. The radial parts 54 serve as guide vanes for conducting air to the inlet of fan impeller 22. Circumferentially disposed about member 59 is a rotatable member 56 guided by flange 5| on housing 26. Member 56 has a continuous peripheral wall apertured at 51 and inward projections 59, whereby passages 58 may be formed in the position of the parts shown in Figs. 10 and 11 communicating with apertures 49. The apertures 51 communicate with the spaces outside the fan assembly on the air inlet side. Attached to member 56 is a hood 42 having a central opening 43 for admission of air to the Member 56 is rotated by a lever 68 having a slot 6| in which a pin 62 slides, which pin is secured to member 56. The lever 69 is pivoted at 63 and moved by a handle 64 on the outside of the casing.

In the position of parts shown in Figs. 10, 11 and 14 the fan impellers are connected for parallel flow of air. Some of the air flows into the fan assembly through opening 43, passing outwardly through the forward fan impeller 2| and through the passages 58 and openings 49 to the outlet of fan member 22. The remainder of the air passes around the outside of hood 42 and inwardly through the openings 51, between the guide vanes 54 into the center of fan impeller 22, and outwardly therethrough to meet the air leaving the forward fan impeller.

If it is desired to couple the fan impellers in series, the handle 64 is turned to rotate member 56 to the position shown in Figs. 16 and 1'7. As shown in Fig. 16 the outer wallparts 56 together with the peripheral parts 55 completely close oi! the flow of air inwardly from around hood 42. 75

ble bellows 61.

. flow through the fan impellers.

aoaaeso All the air must pass through the central inlet 43, and is'carried outwardly in fan member 2i and thence passes within the partially formed passageways 58 which are now inwardly open due to the movement of the peripheral parts 55, thence inwardly between the vanes 54 and to the inlet of the fan member 22. In this position, the passageways 49 are blocked off by the back walls of the spaces 58.

In Figures 18, 19 and 20 is shown an automatic arrangement for rotating the member 56 shown in Figs. 10 'to 17. Within the barrel H is a flexi- The bellows is attached to a ring 68 secured to the inside of the casing, and the interior of the bellows is in communication with the outside atmosphere through an aperture 69. Attached to the closed bottom of the bellows is a spindle ill, to which is attached a member 1| guided in a device 12. Member II is formed with a slot 13 in which moves a pin 14 attached to the hood 42. So long as the pressure diiferential between the outside atmosphere and the intake to the fan is small, the bellows 61 is contracted. The bellows may have internal resiliency tending to contract it, or a spring may be used to contract the bellows. In this condition, the parts are in the position shown in Fig. 18 and the member 56 is so positioned as to provide for parallel flow through the fan impellers. Should the pressure diiferential increase, which is the condition when, for instance, a hose is attached to the cleaner or a small nozzle is tightly pressed against a surface to be cleaned, the free end of the bellows moves inwardly, thus moving the stem 19 downwardly and causing rotation of the pin 14 and member 56 so as to change the connection from parallel to series fiow, thereby providing greater suction effect of the fan assembly.

If a graph were drawn showing operation of parallel and series connected fan members, showing pressure plotted against air quantity, the curves will cross each other. It is desirablethat the automatic changeover take place substantially at the point where such curves cross.

Another embodiment of the invention is shown in Figs. 21-23. The barrel or casing member H is mounted on wheels 89. A handle 8| is provided for moving the cleaner over a floor or carpet. An inner casing 82 is provided within which is contained the dust bag 24. The fan assembly may be provided with the same valvular arrangement as is shown in Figs. 10-17. To move member 56, it is connected to the inner cage 82 and this cage is provided with a projection 83 engageable with an extension 84 on a nozzle 85 insertable in a nozzle connection 86.

A spring 81 is attached to the outer casing and the movable cage 82 and tends to move the inner cage 82 in counter-clockwise direction as shown in 22. A packing 88 is provided between the nozzle opening and the fan assembly to prevent flow of air from the nozzle directly to member 56. Thus all the air entering through the nozzle must pass through the dust bag as shown bythe arrows. Thereafter some of the air may pass out through openings 89 so as to pass inwardly through member 56 as shown in Fig. 11.

Ahose insertable in connection 86 does not have a projection such as 84 and consequently the spring 81 holds the parts inposition for series When, however, the nozzle 85 is inserted as when a floor is to be cleaned, the member 56 is rotated to the position wherein air passes through the fan impellers form shown in Fig. 1.

in parallel. A stop 99 is provided on the nozzle 85 to limit the movement for properly aligning the parts.

In the structure shown in Figs. 24 to 26, the invention is embodied in a cleaner of the general The fan arrangement is substantially that shown in Figs. 10 to 17. The pin 62 is moved by a lever 90 pivoted to the easing II at 9| and operated in a manner analogous to' the arrangement of Fig. 22. A rod 92 is mounted in a bracket 93 secured to casing H and in a plunger tube 94 so as to have longitudinal movement. Rod 92 passes through a hole in lever 90. A spring 95 surrounds rod 92 and is positioned between bracket 93 and lever 90. -A spring 98 surrounds rod 92 and is positioned between lever 90 and a stop 91 on rod 92. The springs urge rod 92 toward the air inlet end of the cleaner and act as a resilient connection between it and lever 90. The plunger tube 94 is adapted to receive a plunger 98 attached to a leg 99 attached to nozzle I00. Leg 99 carries several wheels In! for supporting the cleaner when tilted to the position shown in Fig. 25. Members 92 and 98 fit snugly in tube 94 to prevent leakage. The nozzle I 00 is intended to work where large volume is preferable to high vacuum.

When the hose I1 is fitted into cap l2, there is no plunger 98. Consequently rod 92 is in forward position and pin 62 is moved from the position shown in Fig. 25 and the fan impellers are connected in series. When the large nozzle I90 is directly connected to the cleaner unit, the plunger 98 pushes the rod 92 rearwardly to the position shown in Fig. 25 and the fan impellers are connected for parallel flow of air.

While several embodiments of the invention have been disclosed, it will be obvious that other embodiments of the invention may be made. For example, more than two fan impellers may be provided and connected in series or in parallel. The greater the number of impellers the greater the difference in effect between series and parallel connection. What has been said with respect to a small nozzle plus hose as against a large nozzle without hose obviously applies to small nozzle with a long or narrow hose against large nozzle with short or wide hose.

I claim:

1. A vacuum cleaner comprising a casing, a motor in said casing, a plurality of fan impellers mounted to be driven by said motor, a partition between said impellers having a passage there- 'through connecting the outlet of one fan impeller with the inlet of another fan impeller, a passage therethrough establishing communicationbetween the outlets of the impellers and a passage therethrough establishing communication between the inlets of said impellers, and a valve disc for closing the first mentioned passage and opening the second and third mentioned passages and alternatively for opening the first mentioned passage and closing the second and third mentioned passages.

2. A vacuum cleaner comprising a casing having an air inlet, a nozzle connectible to said air inlet, a plurality 'of fan impellers in said casing, means alterable for connecting said impellers for series or parallel flow, and means operable by the connecting of said nozzle with said inlet to alter the first mentioned means to change the connections between said impellers.

3. A vacuum cleaner comprising a plurality of fan impellers, movable means having two positions for alternatively connecting said impellers for air flow in series or in parallel, means acting to retain said movable means in one of said positions, and means actuable exteriorly of the cleaner for moving said movable means to the other of said positions.

4. A vacuum cleaner comprising a plurality of fan impellers, rotatable means for alternatively connecting the impellers for air flow in series or in parallel, means acting to position the rotatable means for series flow, and means actuable exteriorly of the cleaner for moving the rotatable means to position of parallel flow.

'. A vacuum cleaner comprising a unit enclosing a plurality of fan impellers, rotatable means for alternately connecting the impellers for air flow in series or in parallel, resilient means acting to position the rotatable means for series flow, and means movable on application of a nozzle to the cleaner unit to move the rotatable means to position of parallel flow.

6. A vacuum cleaner having means for alternatively producing large air flow with low suction and small air flow with large suction, and automatic means responsive to the suction pressure produced by the first mentioned means for changing from the one condition to the other.

7. A vacuum cleaner including a plurality of fan impellers, means to connect said impellers for flow of air in parallel or in series, and automatic means responsive to the suction pressure produced by the first mentioned means for actuating the first-mentioned means.

8. A vacuum cleaner including a plurality of fan impellers, conducting means for directing flow of air through said impellers in series, said conducting means being alterable to direct flow of air through the impellers in-parallel, and means responsive to suction variations in the cleaner to alter the conducting means.

9. A vacuum cleaner including a plurality of 5 fan impellers, conducting means for directing flow of air through said impellers in series, said conducting means being alterable to direct flow of air through the impellers in parallel, and a flexible member responsive to atmospheric pressure and pressure within the cleaner for altering the conducting means.

10. A vacuum cleaner including a casing having a suction opening and an exhaust opening,

a dust separating member in said casing between said openings dividing said easing into a dust receiving chamber and a tan chamber, a plurality of impeller fans in said casing including fan housings having inlets and outlets, the

inlet of one of said housings being permanently in communication with the interior space of said casing immediately adjacent to the side of said dust separating member remote from said suction opening and the outlet of the other of said housings being permanently in communication I with the atmosphere, and movable valve means between said impellers for establishing communication between theoutlet 0! said one of said housings and the inlet of said other hous- 3 ing and alternatively for establishing communication between the inlet of said other housing and the said interior space of said casing and between the outlet 01 said one of said housings and the atmosphere.

FREDRIK CARLSTEDI. 

